Contact printing of metallic pattern and its applications on fabricating high-frequency surface acoustic wave (SAW) devices

In this paper, two types of contact-printing methods for micro/nano-lithography are developed and their application on fabricating high-frequency surface acoustic wave (SAW) devices are investigated. First of all, a light-assisted metal film patterning (LAMP) method which transfers a patterned metal film directly from a silicon mold to a substrate is discussed. The pattern transformation relies on both mechanical contact pressure and optical heating at the interface. Metal patterns with 100 nm feature size can be easily transferred in laboratory using simple equipments. Secondly, a contact-transfer and mask-embedded lithography (CMEL) is proposed which cleverly arranges pure mechanical forces and surface energy difference to achieve the patterning of nano-structures on various kinds of substrates. Applications of these two developed methods are demonstrated on the fabrication of high-frequency (~2 GHz) surface acoustic wave (SAW) filters and resonators. Future developments and potential applications of these nanoimprinting and nano-patterning methods will be addressed.